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The mesmerising result is guaranteed to put a smile on your dial. More amazing still is the striking similarities between this kooky click-clacking and all other forms of synchronisation, from pace-maker cells firing to fireflies flashing.

A single metronome ticking away on by itself is nothing much to get excited about. But check out this Studio3 video to see what happens when you put five metronomes together!

A single metronome ticking away on by itself is nothing much to get excited about.

Set two or more identical metronomes up in a row and things get a bit more interesting, so here's the challenge. Can you get all your metronomes to tick in perfect unison?

Try as you might, you won't succeed but it's not because you don't have enough hands. Even an octopus can't do make a bunch of metronomes tick together because although they appear to be identical, tiny variations between them will always cause them to drift out of phase.

There is a nifty solution and surprisingly simple solution to this kooky challenge. Set the metronomes on a piece of stiff Styrofoam or a thin plank of wood resting on a pair of empty soft drink cans, sit back and watch the wonder of spontaneous synchronisation unfold.

The metronomes are now 'coupled' by virtue of the simple fact that the plank they are all resting on can move causing each of their swinging pendulums to either accelerate or decelerate. In no time, the metronomes are tick-tocking in perfect synchrony and will remain that way until they run out of puff. If you've got more metronomes, then don't stop at five. Mathematical models predict that 100 or more metronomes will synchronise almost as quickly as two. Amazing!

What's going on?

There's something strangely mesmerising about a row of metronomes ticking to-and-fro in perfect synchrony. Perhaps it's our subconscious mind presuming there must be some form of intelligence behind the show. We are instantly captivated by the synchronised, collective movements of large groups of animals like schools of fish and flocks of starlings, and rightfully impressed by stunt pilots flying in perfect formation, or marching bands striding in perfect unison, or synchronised swimmers splashing in pretty patterns.

There is, of course, nothing 'intelligent' about a metronome but their synchronised clicking is deeply linked to all other forms of spontaneous synchronisation in almost any system imaginable.

The Dutch clockmaker, Christiaan Huygens first reported the spontaneous synchronisation of two pendulum clocks in a letter to the newly founded Royal Society, dated 27 February 1665. He reported "an odd kind of sympathy" between two maritime pendulum clocks suspended "by the side of each other" from a wooden beam.

Huygens noticed that, no matter how he set the clocks in motion, they would always, eventually, swing with exactly the same frequency but 180 degrees out of phase. If he disturbed one pendulum, the anti-phase was restored within thirty minutes and, then, remained again indefinitely.

Huygens lacked the mathematical tools to describe the phenomenon because those tools had not yet been invented but in 2002, researchers discovered that the original observation had been yet another remarkable scientific fluke. Had Huygens' clocks weighed just a bit more, or less, or been suspended from a slightly stiffer or saggier beam, or been just a bit less precisely identical, the synchronisation he observed could and would not have occurred.

Huygens did correctly deduce that his clocks were somehow, although imperceptibly, affecting each other via the support beam they shared. With metronomes on a rolling plate, this 'coupling' is much more obvious because you can see the plate rolling back and forth. Each metronome's swing affects all the others causing them to either accelerate or decelerate, which you can clearly see in their increasing or decreasing amplitudes until all are perfectly synchronised.

This is all relatively easy to explain in plain English but calculating the variables that determine whether or not the phase-locking will ensue is a fiendishly tricky business. Metronomes and pendulum clocks are non-linear, self-sustained oscillators and non-linear mathematics is extremely complicated.

Fortunately for the rest of us, there are people who just love to contemplate such mathematical nightmares and they've been making amazing discoveries that extend well beyond the kooky clicking of metronomes and clocks to all kinds of fascinating phenomena such as the synchronisation of circadian rhythms to external lighting, the synchronisation of foetal and maternal heart-rates, the synchronised flashing of fireflies and the spontaneous synchronisation of large audiences clapping in appreciation of a brilliant concert, to name but a few.

And if you can get your hands on ten or more metronomes, we'd love to see your video of them clicking and clacking in synchrony, because, well, we've only got five!

See more Surfing Scientist on Studio3! Head over to Studio3 on ABC3 to see more Surfing Scientist tricks during National Science Week. And kids, while you're there, check out the Make It Video Challenge. Make your own marble run and take a video of it to show off your mad skills. The best vids will get published on Studio3's website.